Clinical trial of an inhibitor of RAGE-Aβ interactions in Alzheimer disease

Abstract

Objective: To examine safety, tolerability, and efficacy of PF-04494700, an inhibitor of the receptor for advanced glycation end products (RAGE), in mild to moderate Alzheimer disease (AD).Methods: Double-blind, placebo-controlled trial at 40 academic centers (United States). Subjects with AD and Mini-Mental State Examination score 14-26 were randomized to PF-04494700 60 mg/day 3 6 days, then 20 mg daily (high dose); 15 mg/day 3 6 days, then 5 mg daily (low dose); or placebo, for 18 months. Clinical and laboratory measures were used to evaluate safety and tolerability. The primary efficacy measure was the Alzheimer's Disease Assessment Scale-cognitive (ADAScog). Secondary measures assessed clinical stage, function, behavior, MRI, and CSF biomarkers.Results: A total of 399 subjects were randomized. In a prespecified interim analysis, when 50% of subjects had completed the 6-month visit, the high dose was associated with confusion, falls, and greater ADAS-cog decline and was discontinued. A second prespecified analysis compared lowdose and placebo groups for futility and safety approximately 12 months after all subjects were randomized. This analysis met criteria for futility, and treatment was discontinued. There were no safety concerns in the low-dose group. Analyses including post-futility data showed decreased decline on the ADAS-cog in the low-dose group at month 18. Other clinical and biomarker measures showed no differences between low-dose treatment and placebo.Conclusions: PF-04494700 at 20 mg/d was associated with increased adverse events and cognitive decline. At 5 mg/d, PF-04494700 had a good safety profile. A potential benefit for this low dose on the ADAS-cog is not conclusive, because of high dropout and discontinuation rates subsequent to the interim analyses.

Development of a core outcome set for disease modification trials in mild to moderate dementia: a systematic review, patient and public consultation and consensus recommendations

“…The majority of trials (n = 94) used at least one cognitive outcome, 25,27-29, 51,52,55,57,64,66,68,75,78,[86][87][88][89][90][91][92][93]97,104,106,107,110,112,115,118,119,121,123,125,126,130,131,133,134,[137][138][139][140]143,145,146 with a variety of 16 measures used. ADLs were measured in 55 trials, using 12 measures.…”

“…ADLs were measured in 55 trials, using 12 measures. 27,28,33,37,41,45,46,49,51,52,54,55,57,59,61,63,64,66,68,77,78,81,[85][86][87][88][89][90]92,97,104,[106][107][108][110][111][112]114,115,118,119,[121][122][123][124][125]128,134,135,137,138,[142][143][144][145] Biological markers were measured in 51 trials using a variety of nine biological t...…”

“…29,31,33,37,40,43,47,[53][54][55]59,63,66,[68][69][70][71]73,77,78,81,85,86,89,93,95,96,98,101,[103][104][105][109][110][111][112][113]115,116,121,122,[129][130][131][132]137,[139][140][141]144,145 Eleven of the published trials measured quality of life, using one of three outcomes. 28,33,66,68,78,…”

Ligands of Receptor for Advanced Glycation End-Products Produced by Activated Microglia are Critical in Neurodegenerative Diseases

“…TransTech Pharma also developed PF-04494700, which inhibits RAGE/Aβ-42 binding. This agent, which is administered orally, crosses the BBB and helps reduce Aβ accumulation and spatial memory defects [71].…”

“…RAGE ligands can also be used to support diagnoses of AD or PD. Generally, MRI and cerebrospinal fluid (CSF) biomarkers related to AD, do not provide evidence of neurodegenerative change or amyloid clearance [71,72]. However, it has been reported that some RAGE ligands might be useful diagnostic targets.…”